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Questions in the section

Does AT&T support delivery receipts?

Do the users of my app need a special license or agreement before using it to send SMS messages?

Is it possible to get a higher transaction rate for my app?

What is the maximum length of an SMS message that is currently supported by the SMS API?

What is a custom short code?

How quickly are messages delivered?

Can I associate a custom short code with my application instead of the default short code that is provided by the system?

How long will the delivery status of a previously sent SMS message be available for an application to query?

Can I require that a user of my application respond to a message?

Can the SMS API provided by AT&T be used to talk between devices?

What happens when the phone is switched off when I send an SMS message?

Am I able to send messages using a common short code (five or six digits) that I already have?

What happens when an SMS message cannot be delivered to the destination customer on the first attempt?

Can I send messages to users on other carriers?

When I send a message, who does the end user see as the source of the message?

Can I request delivery receipts for multiple recipients of a single message?

Will the end user (AT&T Wireless customer) who receives a message from my application and sends messages to my application be charged for sending and receiving these messages? test

How do I query the status of the message when I send the same message to multiple recipients?

How can my application access the SMS messages that are sent by AT&T Wireless customers to the short code associated with my application?

How often do I need to invoke the Get SMS method?

AT&T SMS API FAQs

Does AT&T support delivery receipts?

Yes, AT&T supports delivery receipts. There are two ways of getting the delivery status of an SMS message:

  • Polling mechanism—Where the developer application polls on a regular basis with the given message id, to check the status of the sent message.
  • Callback Notification mechanism—Where the developer application registers an SMS Delivery status notification URI against a given short code in the MyApps page of the developer program website, and a near real-time notification is sent to the application listener from the AT&T API Platform when the message reaches its final state.
Updated: 10/23/2017
Created: 10/22/2017
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Do the users of my app need a special license or agreement before using it to send SMS messages?

No special considerations are required as long as the user has a valid AT&T mobile plan and is an AT&T subscriber.

Updated: 10/23/2017
Created: 10/23/2017
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Is it possible to get a higher transaction rate for my app?

See the transaction limits for the various environments. If these limits do not meet your needs, please enter a developer support ticket requesting a revised limit. Depending on your business case, the Support Team may be able to customize the transaction limits.

Updated: 10/23/2017
Created: 10/23/2017
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What is the maximum length of an SMS message that is currently supported by the SMS API?

The maximum length of an SMS message that is currently supported by the SMS API is 4096 (8-bit) characters.

Updated: 10/23/2017
Created: 10/23/2017
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What is a custom short code?

A custom short code is a short code that a developer wants to associate with their application that is different from the default 8-digit short code provided by the AT&T API Platform.

If the custom short code is, as is common, a 5-digit or a 6-digit short code that is managed by usshortcodes.com to be used for cross-carrier messaging, it must be leased by the developer from usshortcodes.com and the developer must provide proof to AT&T that they own the short code before it can be associated with their application on the AT&T API Platform.

If the custom short code being requested by the developer is not a 5-digit or 6-digit short code, then AT&T determines whether the code is available, and whether it is willing to associate that short code to the application. If AT&T approves the custom short code for the given application, the application may incur additional charges.

There are two types of short codes that may be assigned to your application:

  • Online short code: This short code is assigned to your application by default. It is also assigned if you provide a listener URL for Mobile Originated SMS messages so that you get notifications in real time.
  • Offline short code: This short code is assigned if you are polling for messages or if you did not provide a listener URL for the incoming Mobile Originated SMS messages.
Updated: 08/17/2017
Created: 08/16/2017
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How quickly are messages delivered?

Most messages that are delivered to a device which is turned on and connected to the AT&T Wireless network are delivered quickly, often in seconds. However, the delivery time needed for individual messages varies with factors such as network load, user location, and the network connectivity of the device.

Updated: 08/17/2017
Created: 08/17/2017
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Can I associate a custom short code with my application instead of the default short code that is provided by the system?

Yes. You can submit a request to associate a custom short code with your application. In the case of 3, 4, 7, and 8 digit short codes, the AT&T short code management team checks to see whether the code is available so it can be used for your application. This process typically takes 1-2 weeks. If it is a 5 or 6 digit short code, you may have to lease it from https://www.usshortcodes.com and then place a request using the short code management functionality that is available in the MyApps page of the developer web portal interface.

Updated: 02/15/2017
Created: 02/14/2017
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How long will the delivery status of a previously sent SMS message be available for an application to query?

If the application is using the polling mechanism to obtain the status, the delivery status will be available until one of the conditions below is met:

  1. 30 minutes has elapsed after the message has reached its final state OR
  2. You have queried and retrieved the status once after the message has reached its final state

If the application is using the callback operation, by registering the listener endpoint to receive the status, the delivery status will be automatically delivered to the application. On getting an acknowledgment from your application server, the status is removed from the AT&T server.

Updated: 02/15/2017
Created: 02/15/2017
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Can I require that a user of my application respond to a message?

No, that is up to the user of the application.

Updated: 02/15/2017
Created: 02/15/2017
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Can the SMS API provided by AT&T be used to talk between devices?

No. The SMS API sends SMS messages to one or more AT&T Wireless mobile devices. Messages can be sent from one application to another application, or one short code to another short code.

Updated: 02/15/2017
Created: 02/15/2017
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What happens when the phone is switched off when I send an SMS message?

The message is queued and retried for delivery in periodic intervals for up to 72 hours. Once the maximum period of 72 hours is reached, the message is expired and deleted from the retry queue. If the application has registered an SMS delivery notification callback URI, a final delivery notification status will be sent to that endpoint in near real time. The value of the delivery notification status will be “DeliveredToTerminal” if the message is successfully delivered to the handset and “DeliveryImpossible” if the message has expired after 72 hours without successful delivery to the handset.

Updated: 02/15/2017
Created: 02/15/2017
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Am I able to send messages using a common short code (five or six digits) that I already have?

It is possible to use custom short codes (including common short codes) with an application; provided that they are leased or owned by you from Neustar and also approved, as well as configured, to be associated with your application by an AT&T administrator. By default, you are provided one short-code with an application with the capability of adding or removing up to 5 short codes.

Updated: 02/15/2017
Created: 02/15/2017
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What happens when an SMS message cannot be delivered to the destination customer on the first attempt?

The message is queued up in the AT&T network and is retried on a periodic interval until a configured maximum period (normally 72 hours) is reached. After the configured retry period is exhausted, the SMS message expires. When the SMS message is expired in the network, the delivery status of the message is set to DeliveryImpossible for a given recipient.

Updated: 02/15/2017
Created: 02/15/2017
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Can I send messages to users on other carriers?

AT&T Messaging currently does not support sending messages to (or receiving messages from) other carriers customers and is limited to AT&T wireless customers using a wireless device/phone associated with their AT&T account. Messages sent to AT&T wireless customers who are roaming on other carriers' networks will generally be delivered. Delivery of any particular message will depend on factors such as the other carriers' network, support of messaging for roaming AT&T users, and support of the user's device/phone.

Updated: 02/15/2017
Created: 02/15/2017
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When I send a message, who does the end user see as the source of the message?

When you sign up for AT&T messaging, you will be provided the use of an AT&T short code. This typically eight-digit code will be the code that the end user sees as the originator of the message. This same code can be used by end users to reply or send messages to your application.

Updated: 02/15/2017
Created: 02/15/2017
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Can I request delivery receipts for multiple recipients of a single message?

Yes. When a message is sent by an application, the sender can request a delivery receipt for every recipient mobile number.

Updated: 02/15/2017
Created: 02/15/2017
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Will the end user (AT&T Wireless customer) who receives a message from my application and sends messages to my application be charged for sending and receiving these messages? test

Normally, yes. Standard rates would apply. However, it depends on how billing is configured for the short code associated with your application. If you use your own shortcode that is already zero-rated, that billing treatment of the SMS messages will remain in place.

Updated: 02/15/2017
Created: 02/14/2017
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How do I query the status of the message when I send the same message to multiple recipients?

Even though the same message is sent to multiple recipients, the combination of the unique identifier returned in the response of the send request and the destination customer's phone number, can be used to correlate the status of the message sent.

If your application is using the polling mechanism to obtain the status, the response would contain individual status entries for recipients.

If the application is using the callback operation, by registering the listener endpoint to receive the status there would be multiple status notifications (one for each recipient). The delivery status notifications for different recipients may be delivered to your application server at different points in time depending on when those messages are delivered to the individual recipients or expired in the network when they can't be delivered until the specified expiry period is reached.

Updated: 02/15/2017
Created: 02/15/2017
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How can my application access the SMS messages that are sent by AT&T Wireless customers to the short code associated with my application?

Your application has two ways of retrieving messages that are sent by AT&T Wireless customers to the short code associated with your application. One way is where your application will use the polling mechanism to check the inbox associated with your application short code for any new message arrival. The other way is using the callback operation by registering your application listener endpoint to receive the incoming messages.

Your preference has to be implicitly indicated on the preferred mechanism that your application wants to use, while requesting or associating a short code for your application. This is because, for a given short code, both mechanisms could not co-exist for receiving incoming SMS messages.

Updated: 02/15/2017
Created: 02/15/2017
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How often do I need to invoke the Get SMS method?

The answer depends on the volume of messages and how often you are expecting them. The recommended interval is every 5 minutes. If you expect a lot of traffic, you should use the callback operation (for scalability) where your application can register a listener endpoint and where the API Gateway automatically notifies your application of the incoming text message without your application having to frequently poll for the incoming text message.

Note that the preference of polling for the messages or using a callback notification to receive messages must be decided during the time of associating a short code to your application. For a given short code, your application can employ only one mechanism and cannot switch back and forth on the preference for the same short code.

Updated: 02/15/2017
Created: 02/15/2017
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